622 trailer tire pressure

[ironsidebob]

Just woundering what tire pressure most are running on there 622 trailer, new to this trailer, thanks for any info.

[geoshmo]

The manual says 35 psi. I stay close to that.

[jadatis]

I havent the faintest idea what kind of trailer it is, but if you provide me with the weigh of it and the tire-specifications, I will calculate it for you with my made calculator.

Need from trailer next: The maximum allowed total weight , called Gross Vehicle weight rating, but better real determined weight.
Number of tires on the road when driving, and number of axles, my quess is 1 axle with 2 tires on the road.
Then maximum speed you drive with trailer behind, and wont go over for even a minute.

From tires I need next , and can be read from the sidewall: Maximum load or loadindex
Kind of tire to determine the reference-pressure , wich is not the maximum cold pressure of tire, mostly something with "AT 35 psi"
Speedcode of tire.

The 35 psi advice geoshmo makes me suspect the tires to be normal radial car tires , called P-tires in America, in standard load ( SL), for wich the referencepressure( furtheron AT-pressure) is standard 35 psi in American system, maximum cold of such a tire is mostly between 44 psi and 51 psi, and is only given on sidewall of P-tires.

Greatings from a "Dutch Pigheaded Selfdeclared Tirepressure-specialist"
Peter

[3whlLefty]

From another M/C forum. Load the trailer for your trip. Drive it thru some water and observe the footprint the tire leaves. Too narrow means the tire is too hard. Too wide means it could use a bit more PSI. Part of the tire's job is to absorb some of the road bumps.

I suspect that at 35 PSI that trailer will bounce like a basketball going down the road. Kinda hard on the trailer and the cargo.

YMMV

[jadatis]

Googled for the 622 trailer and came to this topic.
http://www.spyderlovers.com/forums/s...1-RT-622-Specs
Found GVWR of 400 lbs, and tires 4.80 X 12 LRB wich I again googled and found tireweight rating of 780 lbs a tire.
So this tire has maximum load 780 lbs ( loadindex 72) AT 35 psi ( because of LRB=loadrange B), speedcode I did not find, but will be high enaugh to drive 160km/99m/h, and for that speed the maximum load is calculated.

Trew this in my made trailer pressure calculator for radial tires, and gave as low as 7 psi /0.5 bar as advice.
this is because the tires are pretty oversised. 2 are allowed to carry 2x780 lbs= 1560 lbs up to max speed of tire AT 35 psi.
You only need 400 lbs with 40 lbs on tonge
My spreadsheet calculates with an extra save formula for radial tires, and ads 10% to the loads for reserve, for things like , pressure loss in time, unequall load R/L etc.
So in case this tire is bias ply or whatever called, this would even need a less save calculation so would give even lower pressure.
So minimum you need if fully loaded, and all the specifications I found where right, is 7 psi.
Higher pressure is not bad for the tires, and good for fuel saving, but 35 psi would give a dancing trailer behind the Spider, wich will effect your driving experiënce. 10 to 15 psi though would not be giving terrible bumping , so if you are scared to go that low , use 10 to 15 psi , but sertainly 35 psi is not needed by far.

So check if everything I found was right, and if so , you can use this low pressure.